(CNN) -- A Florida judge on Monday signed amended court documents mandating that Casey Anthony return to Orlando to serve a year of probation stemming from her check fraud conviction.

"From my reading of this, she should be reporting to probation in Orlando probably within 72 hours," Orange County Circuit Judge Stan Strickland said in signing the documents, according to the Orlando Sentinel.

The action came after an apparent misunderstanding in the case.

Anthony pleaded guilty in January 2010 to felony check fraud charges, admitting she stole a checkbook from her friend Amy Huizenga and wrote five checks totaling $644.25. At the time, defense attorney Jose Baez asked that Anthony be given credit for time served and be placed on probation.

Strickland apparently intended for the supervised probation to begin after Anthony's release from custody, said Randy Means, spokesman for the Orange County State Attorney's Office. But the order signed by Strickland at the time seemed to indicate it was to run while she was in custody awaiting trial on murder charges in the 2008 death of her daughter Caylee.

Cheney Mason, one of Anthony's defense attorneys, said his client's legal team is working to "set aside and vacate the order." He said the order claims Baez and Anthony were present Monday for a hearing -- something Mason said "did not happen."

"From what I can see, it is a fraud," Mason said. "We will be addressing that with all due speed and with aggression as the law, procedures, ethics and judicial canons will allow."

Mason said Anthony's lawyers will seek to "disqualify Mr. Strickland for the second time." The judge had been presiding over her murder trial until April 2010, when he recused himself after the defense accused him of being a "self-aggrandizing media hound" who is biased against Anthony. Orange County Superior Court Chief Judge Belvin Perry Jr. took over, and stayed in that position through the trial.

A jury acquitted Anthony of charges in Caylee's death. The 25-year-old Orlando woman was released from jail July 17. Her whereabouts since then have been unknown.

Means said prosecutors were surprised to receive a letter from the probation office indicating Anthony's probation was completed.

He said there was a miscommunication between what Strickland said at the sentencing and what the court clerk understood. The clerk thought the probation and Anthony's time in custody were to run concurrently.

The documents were amended Monday to add the words "upon release" to Anthony's sentencing documents, the Sentinel said.

Orange County prosecutors will not take a position on whether Anthony should serve probation, Means said, adding the issue is between Strickland, Perry, the probation department and the clerk's office.

"We don't think we have jurisdiction. The court is the sentencer, and if they think it (sentencing) was not followed, they can do something," Means said. "Our position is to leave it up to the court."

A Department of Corrections spokeswoman told CNN affiliate WESH that Anthony must report to Orange County within 72 hours. "We are moving forward to make sure she is following the judge's orders," Gretl Plessinger said.

Anthony's defense attorneys may challenge the move and claim Anthony should not have to serve probation because she already did while in custody, according to the Orlando Sentinel.

Means said the defense would have a strong argument to have the amended sentencing order declared invalid on grounds of double jeopardy. It would be unconstitutional to have Anthony serve another year of probation if technically she already served it while in jail, he said.

Perry has indicated he wants to meet with officials from the Department of Corrections to go over what happened and "make corrections." Means said he does not know what that means, and knew of no pending hearings regarding the issue.

At Anthony's sentencing on the check fraud charges, she was ordered to have no contact with Huizenga, who testified against her during her murder trial.

At her sentencing for the check fraud charges last year, Anthony said, "I just wanted to let everyone know that I'm sorry for what I did. I take complete and full responsibility for my actions, and I'd like to apologize to Amy. I wish I'd been a better friend."

In Session's Aletse Mellado and Jean Casarez contributed to this report.